Apparatus for sealing submersible devices



2 Sheets-Sheet l I I I MAS G. M YEQS, BY

1, 1954 T. G. MYERS APPARATUS FOR SEALING SUBMERSIBLE DEVICES OriginalFiled July 31, 1942 Aug. 31, 1954 1', MYERS 2,687,907

APPARATUS FOR SEALING SUBMERSIBLE DEVICES Original Filed July 31, 1942 2Sheets-Sheet 2 H 1 511 -I ms 52$ 52$ "3 5 I 54T 68 O 1 515 w: i i m.YZ/OMAS C M YEes,

, INVENTOR.

Patented Aug. 31, 1954 APPARATUS FOR SEALING SUBMERSIBLE DEVIGES ThomasG. Myers, Los Angeles, Calif., assignor to p U. S. Electrical Motors,1110., Los Angelcs, Calif.,

a corporation of California Substituted for abandoned application SerialNo. 453,126, July 31, 1942. This application July 1, 1949, Serial No.102,538

2 Claims.

This invention relates to submersible structures, such as submersibleelectric motors adapted to be lowered in a Well for driving a pumpdirectly connected to the motor.

This application is a division of the application of Thomas G. Myers,Serial No. 453,126, filed July 31, 1942, for Submersible Structure, nowabandoned, the latter application being a continuation-in-part ofapplications filed in the name of Thomas G. Myers on November 8, 1937,Serial No. 173,434, entitled Submersible Structure, now Patent No.2,318,181, Patent No. 2,379,- 648, Patent No. 2,381,615, and November22, 1937, Serial No. 175,896, entitled Sealed Submersible Structure, nowPatent No. 2,309,707.

Usually the material pumped from the well is of such character as to beharmful to the motor should it enter into the motor casing. For example,when water is pumped, it should be kept away from the windings andcontacting parts, so as not to cause electrical circuits to beimproperly established, that would disable the motor. Also, such liquidsusually carry grit, sand or other foreign matter that would quickly ruinthe bearings inside of the motor. Accordingly, it is of considerableimportance to segregate the casing interior as completely as possiblefrom the liquid in which it is submerged.

It is one of the objects of this invention to make it possible, in asimple and effective manner, to insure against entry of the externalliquid to the operating parts of the motor.

It has been proposed in the past to provide rotary seals of variouskinds to effect this result, the seals being disposed around the shaftthat necessarily must extend out of the motor casing. However, since themotor casing is subjected to varying liquid pressure, dependent upon thedepth at which it is submerged, these ordinary seals have been foundquite inadequate. It is another object of this invention to provide amultiple seal effect to insure to a greater degree against failure ofthe seal.

It is another object of this invention to utilize the rotating contactsurface type of seal to supplement a liquid seal.

It is still another object of this invention to provide a combinationliquid seal, such as mercury, and a seal formed by contact between apair of relatively rotatable members, the liquid overlapping the regionof contact.

A further object of the invention is to provide improved seals embodyingrelatively rotatable members, in which transverse flexure of theratating shaft under certain load conditions is per- 2 missible withoutdisturbing the sealing contact between the relatively rotatable members.In this connection, the sealing contact is assured by arrangementproviding one or more supplemental seals.

It is still another object of this invention to improve, in general,seals embodying such relatively rotatablemembers.

This invention possesses many other advantages, and has other objectswhich maybe made more easily apparent from a consideration of severalembodiments of the invention. For this purpose there are shown a fewforms in the drawings accompanying and forming part of thepresentspecification. These forms will now be described in detail, illustratingthe general principles of the invention; but it is to be understood thatthis detailed description is not to be taken in a limiting sense, sincethe scope of the invention is best defined by the appended claims.

Referring to the drawings:

Figure 1 is a view, mainly in longitudinal section, of a structureembodying the invention, shown as submerged in'a well;

Fig. 2 is an enlarged fragmentary sectional view of the structure shownin Fig: 1, and-particularly showing the construction of' a seal for thesubmersible structure;

Figs. 3, 4., 5 and 6 are views similar to Fig. 2, disclosing modifiedforms of sealing structures.

The general character of the submersible structure is illustrated tobest advantage in Fig. 1,

wherein a well casing I'll has a submersible electric motor ll disposedtherein. This motor has to' be connected, for example, to a pump (notshown) for pumping liquid from the-well. "The motor is shown assubmerged in the-well liquid i3, which is usually water.

The motor is most conveniently an induction motor of the squirrel cagetype having-primary or stator windings [4. These windings areadapted tobe connected to a suitable source of power at the top of the wellbymeans'of-a cable I5.

Since the liquid carries foreign particles or dirt, the bearings 16, I7sup-porting'the shaft l2 must be protected from this liquid."Furthermore, the windings M of themotor must also be kept separate fromthis liquid, otherwise the motor to be protected for all conditions ofoperation as regards well pressure, levelof the' liquid,*--etc.

This casing structure is shown as formed by a cylindrical body l9 withinwhich the stator I4 is supported. Secured to the lower end of the bodyl9, as by welding, is a lower collar 20, to which is fastened a bearingsupporting housing 2|, as by a series of threaded studs 22. The housing2| provides a stationary collar 23 for supporting the outer race 24 of aradial ball bearing structure l6, the inner race 25 of which is securedon the shaft |2. The rotor laminations 26 are mounted on the shaft I2,as is well understood. Since the body l9 may be made from standard pipe,it is a simple matter to provide a body of the correct length for therating of the particular motor involved.

An upper collar 21 is secured to the top of the body l9, as by welding,and has an upper bearing housing and casing head 28 secured thereto, asby studs 29, in a manner similar to that in which the lower bearinghousing 2| is secured to the lower collar 20. The housing 28 provides anaxially extending boss 30 serving to support the outer race 3| of aradial and thrust ball bearing structure I7, the inner race 32 of whichis mounted on the shaft l2.

The shaft extends upwardly beyond the bearing for connection with apump, not shown. The pump may be connected mechanically to the casing ofthe motor as by the aid of a foot structure 33, supported upon the headmember 28. The shaft passes through the head 28 out of the casingstructure, and it is apparent that precautions must be taken to prevententry of liquid around the rotating shaft |2 at this place. The

manner in which this is accomplished will be described shortly.

The cable |5 extends through a coupling member 35 in fluid tightrelation with the top of the head 28, leading the connections from thewindings I4 upwardly out of the casing structure l8.

It is preferred to have a filling of inert, lubricating liquid 36 withinthe casing structure. For this purpose lubricating oil is convenient,although other suitable liquids may be used. The liquid filling 36 inthe casing may be replenished as desired, for example, by means of asupply pipe 31 connected to a passageway through the head member 28. Thepipe may lead to the top of the well for connection to a source of theliquid under suitable pressure.

It is advantageous that liquid pressure inside the casing structure H!be closely controlled. In this way, there is an assurance that thesealing means provided for the shaft |2 will not be subjected to anyundue pressure difierential. Substantial equalization of pressurebetween the liquid filling 36 in the motor casing and the exteriorliquid I3 is secured by the aid of a structure now to be described.Thus, the bearing housing 2| has an extension. This extension isprovided with a bottom flange 38 having a through aperture 39. Thisaperture is in communication with the interior of a metal bellows 40extending downwardly from the flange 38. This metal bellows is placed influid tight connection with the flange 38, as by the aid of the flange4| and screws 42. It is apparent that the pressure of the oil 36 withinthe casing I8 tends to expand the bellows 40 and the pressure of thewater I3 outside of the casing tends to contract the bellows. Anyvariation in pressure, therefore, that would tend to arise, such as thatdue to temperature variation within the casing, would be equalized byoperation of the bellows 40.

Since the interior of the casing I8 is closed at the bottom by the metalbellows 46, the renewal of the oil within the casing by withdrawal ofthe old oil, is accomplished by providing an emptying pipe 43 for theoil connected to the bottom of the casing, as by being in communicationwith the interior of the bearing housing extension 2|. When it isdesired to replace the old oil, therefore, a circulation is provided bythe aid of appropriate pumping mechanism at the top of the well to forceoil downwardly through the pipe 31 and to remove it through the pipe 43.

The seal 44 disclosed in Figs. 1 and 2 around the upper end of therotary shaft |2 is housed partly within the casing head 28 and partlywithin an upwardly extending tubular member 45, that may be threadedlysecured in the head. This tubular extension is provided with an annularclearance aperture 46 in its end portion 4! around the shaft l2, topermit transverse flexure of the latter under certain load conditions.

The seal structure 44 includes a non-rotary member 48 located within acasing head recess 49 and secured to the casing by screws 50, or thelike. This member extends upwardly along the shaft l2 and has an annularsealing face or surface 5| at its upper end contacted by a companionface 52 on a rotary seal member 53, which is carried by the shaft. Therotary member 53 is secured to the lower end of a flexible or metalbellows 54, the upper end of which is attached to a collar 55 fixed onthe shaft |2. A helical spring |56 may also be disposed around thebellows 54 between the collar 55 and rotary seal member 53, for thepurpose of urging the latter downwardly into firm sealing engagementwith the annular face 5| of the non-rotary member 48.

For the purpose of maintaining the rotary and non-rotary members 53, 48coaxial and in alignment, with their annular sealing faces 5|, 52 inproper engagement with one another, the rotary member is provided with adepending tubular extension or flange 56 telescoped within thenon-rotary member 48. If desired, the cylindrical external surface ofthe flange 56 may make a sliding fit with the cylindrical internalsurface on the non-rotary member 48, to provide a telescopic cylindricalor tubular seal between the flange and the inner wall of the non-rotarymember, which supplements the seal provided between co-engaging annularfaces 5|, 52.

Under certain load conditions, transverse flexure of the shaft I2 ispossible, which may disturb the accuracy of the contact between theannular faces 5|, 52 of the rotary and non-rotary members 53, 48. Toprevent such contact from being disturbed by transverse fiexure of theshaft, and to allow such flexing to occur without interfering with theshaft seal, a substantial annular clearance space 51 is provided betweenthe exterior of the shaft l2 and the interior of the rotary members 53,and its depending tubular extension 56. A substantial annular clearancespace 58 is also provided between the shaft and head 28. Since therotary member is connected to the shaft through the flexible metalbellows 54, the shaft |2 may be deflected transversely withoutcontacting or interfering with the position of the rotary member 53relative to the non-rotary member 48. Any tendencies for the transverseflexing of the shaft to shift the rotary member 53 transversely of thenon-rotary member 48 is prevented by the telescopic fit of the dependingextension or flange 56 within the non-rotary member 48.

The form of shaft seal disclosed in Fig. 3 is similar to the oned-isclosed'in Fig. 2 Hdwever, anadditional heavy liquid" seal isprovided.

As shown in Fig. 3', the non-rotary member '4'8'a is formedwith acircumferential channel or groove 60, and has anouter wall 6| extendingsubstantially above the annular contacting faces 5I-, 52 of the rotaryand non rotary members. The non-rotary member'fits within the casingrecess 49, and has a flange 62 through which screws 63- passinto thecasing head 28 for the purpose of securing-the non-rotary member 48a tothe latter. A tubular casing extension 45a is threadedly'- secured tothe upper end of the nonrotary member 4811:.

The sealing arrangement disclosed in Fig. 3'

is the same as in Fig. 2. However, the ci'rcum ferentialchannel orgroove 50' is filled with a heavy liquid seal 64, which may be' mercuryor carbon tetrachloride; for example, to a level 65 substantially abovethe annular contacting sealing faces 5|, 52. Thisliqui'd' seal 64 is incommunication with-the well fluid I3, that can enter the casingextension 45a. through the clearance aperture 46. However, contaminationof the filling liquid 36 in the casing by the well fluid is prevented bythe three diiferent seals provided. These include the liquid seal 64-circumscribing the rotary member 53a and the non-rotary member 48a; theannular contactingfaces 5|, 52; and the coengaging cylindrical faces onthefiange 56 and non-rotary member 48a.

A. triple seal is also provided in the form of invention disclosed inFig. 4. The casing head 28 is provided with a tubular extension 3511, tothe upper end of which the non-rotary sealing member 48b is secured, asby-means of the screws 65: passing through the flange 66. A collar 61may be'threaded onto the tubular extension 45b, and is provided with anannular clearance aperture 46 around the shaft I2. The non-rotary member4% depends from its flange into the extension 451), and has a lowerannular sealing edge or face 5|?) contacted by a companion annularsealing face 52b on the rotary member 53b carried by the shaft I2. Theupper end of a bellows 54 is attached to the rotary member 53b, and thelower end of the bellows to a collar 68 fixed to the shaft inessentially the same manner as disclosed in Fig. 2. A helical spring I56is disposed between the collar 68 and the rotary member 53b, urging thelatter upwardly into firm sealing contact with the end face 5Ib of thenonrotary member 48b.

In order to maintain the rotary and non-rotary members in properalignment, with their faces 5Ib, 52b effectively sealing against oneanother, a telescopically tubular extension or flange 561) projectsupwardly from the rotary member 53b within the non-rotary member 481).The external cylindrical surface of this projecting member 5822 makes atelescopically sliding fit with the cylindrical inner wall of thenon-rotary member 48b, providing a cylindrical seal therebetween.

As in the other forms of the invention, a substantial annular clearancespace 51bis provided between the shaft I2 and the rotary and nonrotarymembers, to permit transverse flexure of the shaft I2 without disturbingthe sealing contact between the end faces 51b, 52b and cylindrical facesof the rotary and non-rotary members. A third seal may also be provided,in the form of the heavy sealing liquid 64 in the annular space I0between the shaft I2 and the rotary and non-rotary members 53b, 48b, andalso 6. the bellows 54'. This liquid be the annular space I0 throughthe-annular cle r ance aperture II' between the shaft I2 and thenon-rotary member 48b. The level I2 of the liquid 64 is above the upperend of the telescopic flange 56b.

As a result of the arrangement described,=the well fluid I3 is preventedfrom entering the (as: ing by the liquid seal (the cylindrical seal, andthe end seal 5Ib,'52b.

In the embodiment illustrated in Fig. 5', rotary and non-rotary members53b, 481) are ar: ranged in essentially the same'manner as Fig. 4.However", provision is madefor providing a" liquid seal around theexterior ofthe rotary and non-rotary members. To provide sucharrangement, an outer cup-shaped member or (rbntainer I3 is secured tothe shaft I2 below thebellows" 54 and spring I56, and extends upwardlyaround the rotary and non-rotary members 53b, 48b to a pointsubstantially above the annular Contact ing faces 5Ib, 52b; Thecylindrical portion of the container I3 is spaced outwardly fro'm'therotary and non-rotary members to provide an annular chamber 14' that canbe filled with the sealing liquid I5 to a'le'vel I6 substantially abovethe location of the annular contacting races.

In Fig. 5, the liquid filling 36" in' the casing prevented fromcontacting the sealing faces'5lb, 52b by the liquid seal '15. In'th'is"instance, the' three seals are still present, consisting of the outerliquid seal I5, the annular 'end' contacting faces 5Ib, 52b andlthecylindrical contacting faces of the fiange 56b and'non-"rotary member5817.

In Fig. 6, the arrangement is essentially the same as in Fig. 5.Inaddition, an' inner liquid seal II is provided in the annular spacebetween the'shaft I2 and the rotary "andnoh-rotarymerii bers 53b, 48b.The level 18 of this seal is above the upper end of the telescopicflange 56b, to prevent the well liquid I3 from coming in contact withthe circumferential sealing surfaces. Thus, both the well liquid I3 andthe liquid filling 36 in the casing are prevented from contacting thesealing surfaces. In Fig. 6, a total of four seals are present,including the inner and outer liquid seais, the annular end seal and thecylindrical sea In order to prevent leakage of the liquid seals from thecontainer 13a, the latter may be formed of one piece, as disclosed inFig. 6, with the bottom portion I9 engaging a shoulder of the shaft I2,and interconnecting the inner and outer container walls 8|, 82 whichextend upwardly from the bottom or base. The inner wall 8| projectsthrough the central aperture II of the nonrotary member 482), where itis engaged by a nut 83 threaded on the shaft, which forces the containerI 3a against the shoulder 80 and clamps the container to the shaft. Therotary and nonrotary members 5317, 48b, and the bellows 54, in efiect,form an intermediate wall separating the inner and outer sealing liquids11, 15.

Those forms of the invention shown in Figs. 4, 5 and 6 are described ina divisional application, Serial No. 380,034, filed in the name ofThomas G. Myers on September 4, 1953, and entitled Apparatus for SealingSubmersible Devices.

The inventor claims:

1. In a seal structure for a submersible structure: a casing segregatingan interior space from an exterior space; a rotary shaft extending fromthe casing to the exterior space; an annular nonrotary member secured tothe casing and having an opening through which the shaft extends, saidopening defining with said shaft an annular space; a rotary memberhaving an inner annular flange extending into said annular space and inannular engagement with said non-rotary member at the opening thereoffor maintaining alignment between said rotary and non-rotary members;there being clearance between said inner annular flange of said rotarymember and said shaft; a collar secured to the shaft in the exteriorspace; an expansible flexible member surrounding the shaft and mountingsaid rotary member at one end and secured to said collar at the oppositeend; said rotary and non-rotary members having opposed annular sealingsurfaces; said non-rotary member having an integral outer circularflange terminating at a level above said opposed sealing surfaces anddefining an annular channel surrounding said sealing surfaces; a liquidof high specific gravity in said channel; and resilient means engageablewith the collar and said rotary member for urging said sealing surfacesinto intimate contact.

2. In a seal structure for a submersible structure: a casing segregatingan interior space from an exterior space; a rotary shaft extending fromthe casing to the exterior space; an annular nonrotary member havinginner and outer annular flanges extending upwardly in a verticaldirection, said outer flange extending upwardly beyond the level of saidinner annular flange; said inner ann'ular flange forming a componentsealing surface at its upper end; said non-rotary member having 7 acentral opening through which said shaft extends, there being asubstantial clearance of said shaft in said opening to provide anannular space; a rotary member carried by the shaft for rotationtherewith; said rotary member surrounding said shaft and having an innerannular flange telescopingly received in said annular space and inannular engagement with said non-rotary member at the opening thereoffor maintaining alignment between said members; there being clearancebetween said inner annular flange of said rotary member and said shaft;said rotary member having an annular component sealing surface engagingsaid sealing surface of said nonrotary member; said rotary member havinga portion extending upwardly from its sealing surface, and forming, withsaid inner and outer flanges of said non-rotary member, an annularchannel extending above said sealing surfaces; and a sealing liquid ofhigh specific gravity and substantially inert substantially filling saidchannel whereby the level of said sealing liquid is above said sealingsurfaces and the upper surfaces and the upper surface of said liquid isin communication with the exterior space.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,363,378 Vuilleumier Dec. 28, 1920 1,845,363 Thompson Feb.16, 1932 1,850,571 Shively Mar. 22, 1932 1,989,548 Coberly Jan. 29, 19352,035,073 Karrer Mar. 24, 1936 2,057,381 Kenney et a1 Oct. 13, 19362,318,181 Myers May 4, 1943 2,354,874 Myers Aug. 1, 1944 2,379,648 MyersJuly 3, 1945 2,381,615 Myers Aug. 7, 1945 FOREIGN PATENTS Number CountryDate 484,628 Germany Oct. 17, 1929 664,854 France Apr. 29, 1929

